U.S. patent number 6,602,704 [Application Number 10/178,422] was granted by the patent office on 2003-08-05 for sample contact plate with latchable cover.
This patent grant is currently assigned to bioMerieux, Inc.. Invention is credited to Frank Cammarata, III, Anthony J. Donovan, Douglas E. Maxwell.
United States Patent |
6,602,704 |
Maxwell , et al. |
August 5, 2003 |
**Please see images for:
( Certificate of Correction ) ** |
Sample contact plate with latchable cover
Abstract
Contact plates are provided including a base member and a lid.
The base member has a sidewall extending circumferentially around a
peripheral edge portion thereof to define a sample receiving area.
The lid has a sidewall extending circumferentially around a
peripheral edge portion thereof. A plurality of ribs extend from an
inner surface of the sidewall of the lid. The ribs are configured
to provide an interference fit engagement between the sidewall of
the base member and the sidewall of the lid when the lid is
attached to the base member.
Inventors: |
Maxwell; Douglas E. (Itasca,
IL), Cammarata, III; Frank (Cary, IL), Donovan; Anthony
J. (Bartlett, IL) |
Assignee: |
bioMerieux, Inc. (Durham,
NC)
|
Family
ID: |
27623128 |
Appl.
No.: |
10/178,422 |
Filed: |
June 24, 2002 |
Current U.S.
Class: |
435/305.4;
435/288.3; 435/309.1; 435/309.4 |
Current CPC
Class: |
C12M
23/10 (20130101); C12M 23/38 (20130101) |
Current International
Class: |
C12M
1/26 (20060101); C12M 1/22 (20060101); C12M
001/22 () |
Field of
Search: |
;435/288.3,288.4,305.1,305.2,305.3,305.4,309.1,309.4 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Redding; David A.
Attorney, Agent or Firm: Patel; Samir R. Glatz; Robert
W.
Claims
What is claimed is:
1. A contact plate comprising: a base member having a sidewall
extending circumferentially around a peripheral edge portion
thereof to define a sample receiving area; and a lid having a
sidewall extending circumferentially around a peripheral edge
portion thereof and a plurality of ribs extending from an inner
surface thereof, the ribs being configured to provide an
interference fit engagement between the sidewall of the base member
and the sidewall of the lid when the lid is attached to the base
member;
wherein the base member further comprises a contact surface
extending around the sidewall of the base member outside the sample
receiving area and wherein the lid further comprises a flange
member outwardly extending from a bottom end of the sidewall of the
lid and positioned to engage the contact surface of the base member
when the lid is attached to the base member.
2. The contact plate of claim 1 wherein the contact surface of the
base member further comprises a plurality of ribs extending
upwardly therefrom and positioned to engage the flange member of
the lid when the lid is attached to the base member, and wherein
the ribs extending from the contact surface of the base member and
the ribs extending from an inner surface of the lid define an
airflow passage to the sample receiving area when the lid is
attached to the base member.
3. The contact plate of claim 1 wherein the ribs extending from an
inner surface of the lid are configured to provide a retention
force of between about 50 grams and about 2000 grams when the lid
is attached to the base member and the flange member extending from
the sidewall of the lid engages the contact surface of the base
member.
4. The contact plate of claim 1 wherein the ribs extending from an
inner surface of the lid are configured to provide a retention
force of at least about 50 grams when the lid is attached to the
base member and the flange member extending from the sidewall of
the lid engages the contact surface of the base member independent
of the rotational orientation of the lid relative to the base
member on repeated attaching of the lid to the base member.
5. The contact plate of claim 1 wherein the ribs extending from an
inner surface of the lid taper inwardly at a first angle relative
to a central axis of the contact plate and an outer surface of the
sidewall of the base member tapers inwardly at a second angle
relative to the central axis of the contact plate.
6. The contact plate of claim 5 wherein the ribs extending from an
inner surface of the lid have a height relative to the inner
surface of the sidewall of the lid at a bottom end of the lid of
between about 0.02 centimeters (cm) and about 0.04 cm.
7. The contact plate of claim 6 wherein the ribs extending from an
inner surface of the lid have a width of between about 0.04
centimeters (cm) and about 0.09 cm.
8. The contact plate of claim 6 wherein the inner surface of the
lid has a minimum radius about equal to a maximum radius of the
outer surface of the sidewall of the base member.
9. The contact plate of claim 6 wherein the inner surface of the
lid has a minimum radius within about 0.03 cm of a maximum radius
of the outer surface of the sidewall of the base member.
10. The contact plate of claim 6 wherein the first angle is between
about 3.5 degrees and about 4.5 degrees and the second angle is
between about 3.5 degrees and about 4.5 degrees.
11. The contact plate of claim 6 wherein the plurality of ribs
extending from an inner surface of the lid comprises at least 4
ribs.
12. The contact plate of claim 11 wherein the plurality of ribs
extending from an inner surface of the lid comprises 4 ribs
positioned about 90.degree. apart around the inner surface of the
lid.
13. The contact plate of claim 6 wherein the plurality of ribs
extending from an inner surface of the lid comprises at least 12
ribs.
14. The contact plate of claim 13 wherein the at least 12 ribs are
positioned at substantially uniformly offset locations around the
inner surface of the lid.
15. The contact plate of claim 6 wherein the first angle is between
about 3.5 degrees and about 4.5 degrees and the second angle is
between about 3.5 degrees and about 4.5 degrees.
16. A contact plate comprising: a base member having a sidewall
extending circumferentially around a peripheral edge portion
thereof to define a sample receiving area, the sidewall of the base
member including an outer surface having a maximum radius, the base
member further comprising a contact surface extending around the
sidewall of the base member outside the sample receiving area; and
a lid having a sidewall extending circumferentially around a
peripheral edge portion thereof and a plurality of ribs extending
from an inner surface thereof, the sidewall of the lid being
configured to receive the sidewall of the base member, the ribs
being configured to provide an interference fit engagement between
the sidewall of the base member and the sidewall of the lid when
the lid is attached to the base member, the inner surface of the
lid having a minimum radius within about 0.03 centimeters (cm) of
the maximum radius of the outer surface of the sidewall of the base
member, the ribs extending from an inner surface of the lid having
a height relative to the inner surface of the sidewall of the lid
at a bottom side of the lid of between about 0.02 cm and about 0.04
cm and a width of between about 0.04 cm and about 0.06 cm;
wherein the ribs extending from an inner surface of the lid are
configured to provide a retention force of at least about 50 grams
when the lid is attached to the base member and the flange member
extending from the sidewall of the lid engages the contact surface
of the base member independent of the rotational orientation of the
lid relative to the base member on repeated attaching of the lid to
the base member.
17. The contact plate of claim 16 wherein the plurality of ribs
extending from an inner surface of the lid comprises at least 4
ribs.
18. The contact plate of claim 17 wherein the plurality of ribs
extending from an inner surface of the lid comprises 4 ribs
positioned about 90.degree. apart around the inner surface of the
lid.
19. The contact plate of claim 16 wherein the plurality of ribs
extending from the inner surface of the lid comprises at least 12
ribs positioned at substantially uniformly offset locations around
the inner surface of the lid.
Description
FIELD OF THE INVENTION
The present invention relates to devices for holding samples and,
more particularly, to contact plates with lids for enclosing
samples, such as microorganisms.
BACKGROUND OF THE INVENTION
A variety of sampling devices have been developed over the years
for holding an agar media, or the like, in order to test whether
microorganisms are present in a sample. One problem encountered
with existing sampling devices is that the person who is using the
device may have difficulty handling the sampling device and the
sample without introducing contaminants that might affect the
test.
Another difficulty associated with conventional sampling devices is
that it often becomes hard to remove a lid from a dish because of a
moisture seal lock. However, the opposite problem, the lid being
inadvertently detached or removed when it is desired to maintain
the sampling device in a covered state, may also be encountered
with known sampling devices, which may adversely affect the ability
to maintain, handle and/or store the sampling devices.
U.S. Pat. No. 5,854,065 describes one known type of microorganism
sampling device. A base member is provided with a continuous
sidewall providing a holding area for the agar media. A peripheral
support surface extends around the base member at the external
diameter of the base member outside the continuous sidewall. The
lid member of the sampling device has a flange extending around the
external diameter thereof, which includes a plurality of lugs
downwardly extending therefrom that contact the peripheral support
surface of the base member when the lid member is attached and
define a gap allowing for airflow between the lid and base member
to inhibit the creation of a moisture seal lock.
The count-tact Plate.TM. from bioMerieux, Inc. of France is a
further type of microorganism sampling device. The count-tact
Plate.TM. includes a base member with a continuous sidewall
providing a holding area. The base member sidewall includes a
plurality of ribs extending from an outer surface thereof that are
contacted by the lid of the count-tact Plate.TM. when the lid is
pressed onto the base member by a user. The ribs may, thus, operate
to removably connect the lid to the base member.
SUMMARY OF THE INVENTION
According to embodiments of the present invention, contact plates
are provided including a base member and a lid. The base member has
an upwardly extending sidewall extending circumferentially around a
peripheral edge portion thereof to define a sample receiving area.
The lid has a sidewall extending circumferentially around a
peripheral edge portion thereof. A plurality of ribs extend
inwardly from an inner surface of the sidewall of the lid. The ribs
are configured to provide an interference fit engagement between
the sidewall of the base member and the sidewall of the lid when
the lid is attached to the base member.
In further embodiments of the present invention, the base member
includes a contact surface extending around the sidewall of the
base member outside the sample receiving area. The lid includes a
flange member extending outwardly from a bottom end of the sidewall
of the lid and positioned to engage the contact surface of the base
member when the lid is attached to the base member. The contact
surface of the base member may also include a plurality of ribs
extending upwardly therefrom and positioned to engage the flange
member of the lid when the lid is attached to the base member. The
ribs of the base member and the ribs of the lid may together define
an airflow passage to the sample receiving area when the lid is
attached to and secured to the base member.
In other embodiments of the present invention, the ribs of the lid
are configured to provide a retention force of between about 50
grams and about 2000 grams when the lid is attached to the base
member and the flange member engages the contact surface of the
base member. The ribs of the lid may be configured to provide a
retention force of at least about 50 grams when the lid is attached
to the base member and the flange member of the lid engages the
contact surface of the base member independent of the rotational
orientation of the lid relative to the base member on repeated
attaching of the lid to the base member.
In further embodiments of the present invention, the ribs of the
lid taper inwardly at a first angle relative to a central axis of
the contact plate. An outer surface of the sidewall of the base
member tapers inwardly at a second angle relative to the central
axis of the contact plate. The first angle and the second angle are
selected to provide the interference fit engagement. The first
angle may be between about 3.5 degrees and about 4.5 degrees and
the second angle may be between about 3.5 degrees and about 4.5
degrees.
In other embodiments of the present invention, the ribs of the lid
have a height relative to the inner surface of the sidewall of the
lid at a bottom side of the lid of between about 0.02 centimeters
(cm) and about 0.04 cm. The ribs extending from an inner surface of
the lid may have a width of between about 0.04 centimeters (cm) and
about 0.09 cm. The inner surface of the lid may have a minimum
radius about equal to a maximum radius of the outer surface of the
sidewall of the base member. The inner surface of the lid may have
a minimum radius within about 0.03 cm of a maximum radius of the
outer surface of the sidewall of the base member.
In further embodiments of the present invention, the plurality of
ribs extending from an inner surface of the lid includes at least 4
ribs. In some embodiments, 4 ribs may be provided positioned about
90.degree. apart around the inner surface of the lid. In other
embodiments at least 12 ribs are provided. The at least 12 ribs may
be positioned at substantially uniformly offset locations around
the inner surface of the lid.
Objects of the present invention will be appreciated by those of
ordinary skill in the art from a reading of the figures and the
detailed description of the embodiments that follow, such
description being merely illustrative of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which form a part of the specification,
illustrate embodiments of the present invention. The drawings and
description together serve to fully explain the invention. In the
drawings,
FIG. 1 is a perspective view of a contact plate in accordance with
embodiments of the present invention;
FIG. 2 is a perspective view of a lid and a base member of a
contact plate in accordance with embodiments of the present
invention in an open position;
FIG. 3 is a planar top view of a lid of a contact plate in
accordance with embodiments of the present invention;
FIG. 4 is a planar top view of a base member of a contact plate in
accordance with embodiments of the present invention;
FIG. 5 is a partial cross-sectional view of a lid and a base member
of a contact plate in accordance with embodiments of the present
invention in an open position; and
FIG. 6 is a partial cross-sectional view of the lid and a base
member of FIG. 5 in a closed position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention now will be described more fully hereinafter
with reference to the accompanying drawings, in which embodiments
of the invention are shown. This invention may, however, be
embodied in many different forms and should not be construed as
limited to the embodiments set forth herein; rather, these
embodiments are provided so that this disclosure will be thorough
and complete, and will fully convey the scope of the invention to
those skilled in the art. In the drawings, like numbers refer to
like elements throughout. The terms "upwardly", "downwardly",
"vertical", "horizontal", "bottom", "top" and the like are used
herein for the purpose of explanation only and have there normal
orientation with reference to use of the contact plates in sample
testing.
Referring now to FIGS. 1-4, a contact plate in accordance with
embodiments of the present invention will now be described. The
contact plate 100 includes a lid 102 and a base member 104. The
base member has a sidewall 130 (FIG. 2) extending circumferentially
around a peripheral edge portion of the base member 104. As seen in
FIG. 2, the side wall 130, in cooperation with the bottom wall
(floor) 131, defines a sample receiving area 135 in which a sample
growth media, such as agar, and/or samples to be evaluated may be
contained. Preferably, a continuously extending side wall 130 is
provided so that a growth media may be placed in the sample
receiving area 135 in an agar form. The side wall 130 includes an
outer surface 134 and an inner surface 132.
The base member 104, as shown in FIG. 2, further includes a contact
surface 110 extending around the side wall 130 outside the sample
receiving area 135. A plurality of ribs 112 extend upwardly from
the contact surface 110 and are positioned to engage a flange
member 108 of the lid 102 when the lid 102 is attached to the base
member 104 as illustrated in FIG. 1. Also shown in FIG. 2 or FIG. 4
are numerical indicia 140, grid indicia 142 and alpha numeric
indicia 144, all of which may be used, for example, by reference to
the grid indicia 142.
Lid 102 has a sidewall 106 extending circumferentially around a
peripheral edge of the lid 102. A plurality of ribs 120 extend from
an inner surface 122 (FIG. 3) of the side wall 106. The ribs 120
are configured to provide an interference fit engagement between
the side wall 130 of the base member 104 and the side wall 106 of
the lid 102 when the lid 102 is positioned and secured/attached to
the base member 104.
Referring now to the partial cross sectional views of FIGS. 5 and
6, a contact plate 200 according to embodiments of the present
invention will be further described. FIG. 5 shows a lid 202 and a
base member 204 in an open/unattached/unsecured position, while
FIG. 6 shows the lid 202 and base member 204 in a
closed/secured/attached position with an interference fit
engagement holding the lid 202 coupled to the base member 204. Like
numbered features, of the 200 series, illustrated in FIGS. 5 and 6
correspond generally to the counterpart numbered features of the
100 series described with reference to FIGS. 1-4 above and will not
be further described herein.
As shown in FIGS. 5 and 6, by the cross-sectional view of the lid
202 through one of the ribs 220 and the cross-sectional view of the
base member 204 through one of the ribs 212 on the contact surface
210 of the base member 204, the ribs 220 have a height h extending
inwardly from an inner surface 222 of the side wall 206. The ribs
120, 220 similarly have a width w as illustrated in FIG. 3. As
shown in FIG. 5, the ribs 120, 220 taper from a smaller height at a
bottom end 255 of the lid 202 to a greater height at a top end 260
of the lid 202.
As shown in FIG. 6, the ribs 212 extending from the contact surface
210 of the base member 204 and the ribs 220 extending from the
inner surface 222 of the lid 202 define an airflow passage 250 to
the sample receiving area 235 when the lid 202 is attached to the
base member 204. As also shown in FIG. 6, an interference fit
engagement region 265 is provided between the ribs 220 and the
outer surface 234 (FIG. 5) of the side walls 230 (FIG. 5). The side
walls 230 further include an inner surface 232 defining the sample
receiving area 235 with a single U-shaped wall member providing the
side wall 230. The sample receiving area 235 is further defined by
the bottom wall 231 on which indicia, such as the indicia 140, 142,
144, may be provided.
As shown in FIG. 5, the outer surface 234 of the base side wall 230
may be tapered at an angle .theta.', tapering in from a maximum
radius 275 of the outer surface 234 of the side wall 230 relative
to a central axis A (FIG. 2) of the contact plate 100, 200. In
addition, the ribs 220 extending from the inner surface 222 of the
lid 202 taper inwardly at an angle .theta. relative to the central
axis A. The inner surface 222 of the lid 202 has an associated
minimum radius 270. The angle .theta. and the angle .theta.' may be
selected to provide the desired interference fit engagement between
the lid 202 and the base member 204 when the lid 202 is positioned
and secured in an attached position over the base member 204 with
the flange member 208 extending from the side wall 206 of the lid
202 engaging the ribs 212 of the contact surface 210 of the base
member 204. In various embodiments, the resulting frictional
retention force is between about 50 grams and about 2000 grams.
It is to be understood that the retention force may be affected by
the angles .theta., .theta.', the height h of the ribs 220 and the
minimum radius 270 and maximum radius 275 of the lid 202 and the
base member 204, respectively. It will be further understood that
the frictional forces providing the interference fit engagement may
be increased by increasing the width w of the ribs 120, 220 as well
as by one or more of increasing the maximum radius 275 of the side
walls 134, 234, by decreasing the minimum radius 270 of the side
walls 106, 206, by increasing the height H of the ribs 120, 220 or
by changing the relative angles .theta., .theta.'.
In particular embodiments of the present invention, the ribs 120,
220 have a height h relative to the inner surface 122, 222 at the
bottom side 255 of the lid 202 of between about 0.02 centimeters
(cm) and about 0.04 cm. The ribs 120, 220 may have a width of
between about 0.04 centimeters (cm) and about 0.09 centimeters
(cm). The inner surface 122, 222 of the lid 102, 202 may have a
minimum radius within about 0.03 cm of a maximum radius of the
outer surface 134, 234 of the side wall 130, 230 of the base member
104, 204. The angle .theta. may be between about 3.5 degrees and
about 4.5 degrees and the angle .theta.' may be between about 3.5
degrees and about 4.5 degrees.
In various embodiments of the present invention, different numbers
of the ribs 120, 220 may be provided on the lid 102, 202. In
various embodiments, there may be at least 4 ribs and at least 12
ribs, as illustrated by the 12 ribs shown for the embodiment
illustrated in FIG. 3. The ribs may be positioned at substantially
uniformly spaced locations around the inner surface 122, 222 of the
side walls 106, 206 of the lid 102, 202. For example, in a 4 rib
embodiment, the ribs 120, 220 may be positioned about 90 degrees
apart around the inner surface 122, 222 of the lid 102, 202.
The lid 102, 202 and the base member 104, 204 may both be molded
from the same material or from different materials. In particular
embodiments of the present invention, the lid 102, 202 and the base
member 104, 204 are comprised of a material selected from the group
consisting of polycarbonate and polystyrene. Preferably, the lid
member 102, 202 and the base member 104, 204 are molded from the
same material.
Processes for molding lids 102, 202 and base members 104, 204 will
be understood by those of skill in the art in light of the
disclosure herein and will not be further described herein.
However, it is to be understood that the side walls 106, 206 and
the side walls 134, 234 as well as other illustrated features of
the contact plates 100, 200 may be provided tapered angles selected
to facilitate molding operations. In such configurations, it is to
be understood that the reference angles relative to the axis A used
for tapering of the features as described herein may affect the
interference force provided and, thus, the specification of the
height h with width w angles .theta., .theta.' and maximum and
minimum radiuses of the engaging features are to be considered with
reference to such angled aspects of the various members, which may
be included to facilitate molding operations.
The inclusion of the ribs 120, 220 extending inwardly from the side
walls 106, 206 of the lid 102, 202 as described herein may provide
potential benefits in facilitating molding and maintenance of molds
used in manufacturing the contact plates 100, 200 of the present
invention. For example, the selection of suitable inserts and other
aspects of the mold for the inventive contact plates 100, 200 may
allow the use of a four cavity, rather than two cavity, mold.
The inventors of the present invention have observed in the prior
art contact plates that some deformation and creep may occur in the
lid 102, 202 over time when subjected to pressure. As a result, in
applications where the lid 102, 202 is removed and reinstalled over
the base member 104, 204 repeatedly, the rotational orientation of
the lid 102, 202 relative to the base member 104, 204 may change
each time the lid 102, 202 is replaced on the base member 104, 204
and the deformation of the lid may cause the retention force
therebetween to change each time. The inventors have found that the
use of the ribs 120, 220 extending from the inner surface 122, 222
of the side walls 106, 206 of the lid, as contrasted with ribs on
the base member, may beneficially provide a retention force of a
desired minimum amount, such as of at least about 50 grams, even on
repeated pressing of the lid 102, 202 over the base member 104, 204
independent of the rotational orientation of the lid 102, 202
relative to the base member 104, 204.
Thus, a contact plate 100, 200 may be provided in accordance with
embodiments of the present invention that provides a holding force
to maintain a lid in a closed position relative to a base member
and the holding force may be maintained at a desirable level to
insure proper holding of the lid on the base member over repeated
use, regardless of the rotational orientation used for the lid
relative to the base member. Such benefits may be provided without
otherwise changing the size and/or shape of the sample receiving
area 135, 235 and the perception of the contact plate 100, 200 by a
user. As a result, the number of accidental openings and
operator-related contamination events may be reduced using an
operator friendly one-touch closure with light pressure on the top
center of the lid 102, 202.
The foregoing is illustrative of the present invention and is not
to be construed as limiting thereof. Although a few exemplary
embodiments of this invention have been described, those skilled in
the art will readily appreciate that many modifications are
possible in the exemplary embodiments without materially departing
from the novel teachings and advantages of this invention.
Accordingly, all such modifications are intended to be included
within the scope of this invention as defined in the claims. In the
claims, means-plus-function clauses are intended to cover the
structures described herein as performing the recited function and
not only structural equivalents but also equivalent structures.
Therefore, it is to be understood that the foregoing is
illustrative of the present invention and is not to be construed as
limited to the specific embodiments disclosed, and that
modifications to the disclosed embodiments, as well as other
embodiments, are intended to be included within the scope of the
appended claims. The invention is defined by the following claims,
with equivalents of the claims to be included therein.
* * * * *